Several drugs targeting ODC1, including DFMO, PG‐11047, and SBP‐101 are under clinical trials for the treatment of breast cancer or other solid tumors.[29, 41] It is noteworthy that our data have demonstrated that genetic or pharmacological inhibition of ODC1 significantly suppresses BCSC population, but does not affect primary tumor growth in animal experiments. Here, ODC1 is linked to breast carcinoma.